• Korean Journal of Weed Science
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• v.7 no.2
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• pp.165-170
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• 1987

This study was undertaken to elucidate the behavior of herbicide bensulfuron-methyl[methyl-2-[[[[[(4,6-dimethoxy pyrimidine-2yl)amino]carbonyl]amino]sulfonyl]methyl]benzoate]in soils. Adsorption of the herbicide in soils was mainly correlated with content of organic matter and clay, and canon exchange capacity. Adsorption distribution coefficient(Kd value) in clay loam soil was greater than those in loam and sandy loam soils. The Kd value decreased in the order of zeolite, bentonite, halloysite and laziolite clay minerals. Bensulfuron-methyl moved to 3cm deep in clay loam soil and 4cm deep in sandy loam and herbicide treated layer was 0 to 2cm profile in the two soils. The decomposition rate of bensulfuron methyl varied with the soil properties. The rate was slower in sterilized soil than in nonsterilized. Addition of organic matters to the soils accelerated the decomposotion. The degradation was more rapid in 30$^{\circ}C$ soil temperature than in 20$^{\circ}C$.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.212-218
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• 1998

An obligately methylotrophic bacterium which produces extracellular polysaccharide (EPS) was isolated through methanol-enrichment culture technique. The isolate was aerobic, nonmotile, and gram negative rod and exibited catalase, but no oxidase, activity. Plasmid, carotenoid, and poly-${\beta}$-hydroxybutyric acid were not found. The guanine plus cytosine content of DNA was 52-56%. The isolate was found to grow only on methanol and monomethylamine. Growth was optimal ($t_d=2.4h$) at $35^{\circ}C$ and pH 6.5 in a mineral medium containing 0.5% (v/v) methanol, 25 mM phosphate, and 0.212% ammonium sulfate. Methanol was assimilated through the ribulose monophosphate pathway. Maximun amount of EPS was produced in cells growing at the mid-stationary growth phase at $30^{\circ}C$ in a mineral medium (PH 6.5) containing 1.0% (v/v) methanol in the CIN ratio of 54.7. Thin-layer chromatographic and high performance liquid chromatographic analysis revealed that the EPS was composed of glucose and galactose. EPS which was not treated with ethanol (Pbe) exhibited stable viscosity under various concentrations of salts and temperatures hut showed high viscosity at low pH. EPS precipitated with ethanol (Pae) was found to be more stable in viscosity than the Pbe at various salt concentrations, temperatures, and pH. The Pae also exhibited higher viscosity than the Pbe and xanthan gum. Scanning electron microscopy revealed that the lyophilized Pbe and Pae have a multi-layered structure and a structure of thick fibers, respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.49-55
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• 2009

Our domestic economy has been developed very rapidly after 1960's. Also, it is dramatically increasing traffic on road and surround environmental issues. Especially, rapid economic growth has been induced large construction of pavement, and bigger and higher traffic for transportation. These are making air pollution, traffic noise and vibration. The social requirement against the revealed road environment and traffic sound reduction is being demanded. Traffic noise of city zone is showed over the environmental specification more than 57%. In order to overcome these situations, the social attention is being increased. The quiet pavement is the same format of permeable pavement, but is not same for functional performance. In this research, it has been carried out to evaluate the fundamental-mechanical properties of hot mix asphalt for quiet pavement. Especially, couple of laboratory tests are conducted like marshall stability, resilient modulus, indirect tensile test, and compaction energy analysis with gyratory compaction curve. Also, two-layer pavement system has been adopted for developing of quiet pavement. The basic performance of hot mix asphalt of quiet pavement show a satisfaction of specification of hot mix asphalt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.467-472
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• 1991

In order to investigate the changes of lipid ingredient and fatty acid content in flint corn by a growth process, total lipids from flint corn(Zea may l.) were extracted, purified and fractionated into three lipid classes (neutral lipid ; NL, glycolipid ; GL, phospolipid ; PL) by silicic acid column chromatography (SACC). Non-polar lipid ingredients and fatty acid contents were determined by thin layer chromatography (TLC) and gas chromatography (GC). And non-polar lipid ingredients were quantitatived by TLC scanner. The crude oil among proximare composition increased 2.74% to 4.43% and NL and PL were fractionated by SACC increased 48.5% to 86.02%, 1.01% to 2.73%, respectively. But GL decreased 50.4% to 11.25%. Neutral lipid ingredients identified monoglyceride, were 1.1~3.7%, 11.9~16.1%, 2.3~4.2%, 16.7~21.5% and 58.5~63.6%, respectively. The major fatty acids of NL were linoleic (48.9~61.0%), oleic(22.3~34.2%), palmitic (10.3~11.7%) acids and stearic, linolenic acids were also detected as minor components. The ratio of total unsaturated fatty acid to total saturated fatty acid presented a higher percentage of 5.87~6.34. The physico-chemical characteristics of flint corn lipids were presented as specific gravity presented 0.920, refractive index 1.468, saponification value 191.2, unsaponificable matter 0.97%, acid value 0.58 and iodine value 124.6, respectively.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.54-54
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• 2019

Color-fleshed potatoes 'Hong-young' and 'Ja-young' were developed by RDA, and it has reported that they have high content of anthocyanin. Additionally they show higher radical scavenging activity compared to white or yellow fleshed potatoes. So it will be expected that the consumption of color-fleshed potatoes gradually increase by pre-peeled potatoes and color potato chips. This study was conducted to enhance the utilization of the tuber of color-fleshed potatoes. At first, we isolated four compounds from the organic solvents soluble layer in ethanol extract of tuber, and their structures were characterized by spectroscopic methods and by comparing their data to those in the literature. Their structures were characterized to be caffeic acid (1), chlorogenic acid (2), gallic acid (3) and protocatechuic acid (4) for the first time reported from this source. These compounds were already reported ingredients but considered to exhibit a high physiological activity. The quantitative determination on the four compounds in tuber of color-fleshed [Hong-young (HY) & Ja-young (JY)] and white-fleshed [Superior (SP)] potatoes samples were measured using HPLC. The concentration of caffeic acid in each total fractionations of HY (184.4 g/g) and JY (435.1 g/g) were higher than in total fractionation of SP (31.1). The concentration of gallic acid in each total fractionations of HY (282.1 g/g) and JY (315.2 g/g) were higher than in total fractionation of SP (143.3 g/g). The concentration of chlorogenic acid contents appeared to be highest in total fractionation of SP (954.2 g/g). The concentration of protocatechuic acid in total fractionation of HY (120.3 g/g) was higher than in each total fractionationss of JY (74.4 g/g) and SP (102.7 g/g). Overall, color-fleshed potatoes had higher amount of physicochemical properties than 'Superior'. Therefore, color-fleshed potatoes are expected to be highly valuable items for the development and applications of a functional food. In addition, these results will provide fundamental information for improving sitological value, and breeding of new cultivar.

• Journal of Sericultural and Entomological Science
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• v.21 no.1
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• pp.36-44
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• 1979

Those studies were examined rearing two varieties on Japanese descent and two varieties of Chinese descent by feeding polluted mulberry leaves, non-polluted ones and water-cleaned ones respectively to find effects of air-pollution on the economic characters of silkworms and analysis of contents of Sulphur and Cadmium in the mulberry leaves and silkworms as followings; 1) Japanese descent of polluted part was delayed about 2.5 days than non-polluted part, Chinese descent was delayed about 4 days or inequal and water-cleaned part was medium in the silkworm larval duration. 2) Results of maximum weight of 5th instal, cocoon layer weight and cocoon weight were decreased in due order non-polluted, water-cleaned and polluted in the factors of mulberry 3) Pupal ratio of Japanese descent was not shown statistical significance, but Chinese descent was revealed it obviously in the factors of mulberry leaves. 4) In the resistance of polluted mulberry leaves, Chinese descent was feeble obviously than Japanese and there were some difference even through among the same varieties. 5) The content of S and Cd of polluted area mulberry leaves was increased about 30% respectively than non-polluted area. 6) The fed part of non-polluted mulberry leaves was S 0.41% and Cd 0.013 ppm water-cleaned part was S 0.47% and Cd 0.024 ppm and polluted part was S 0.52% and Cd 0.042 ppm in the contents of S and Cd of silkworm larvae. 7) The contents of S and Cd didn't make visible injury in mulberry leaves but made it seriously in silkworm larvae. 8) The injury of dust on mulberry leaves was more serious than that of quality of mulberry leaves by air-pollution in the economic characters of silkworm. 9) As above results, Chinese descent should avoid contaminated area and it rearing by water-cleaned mulberry leaves can get noticable results in inevitable case on selection of parents silkworm rearingzone.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.439-447
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• 2019

In this study, experiments were conducted to establish appropriate measures for slopes with high risk of collapse and to obtain results for minimizing slope collapse damage by detecting the micro-displacement of soil in advance by installing a laser sensor and a vibration sensor in the landslide reduction model experiment. Also, the behavior characteristics of the soil layer due to rainfall and moisture ratio changes such as pore water pressure and moisture were analyzed through a landslide reduction model experiment. The artificial slope was created using granite weathering soil, and the resulting water ratio(water pressure, water) changes were measured at different rainfall conditions of 200mm/hr and 400mm/hr. Laser sensors and vibration sensors were applied to analyze the surface displacement, and the displacement time were compared with each other by video analysis. Experiments have shown that higher rainfall intensity takes shorter time to reach the limit, and increase in the pore water pressure takes shorter time as well. Although the landslide model test does not fully reflect the site conditions, measurements of the time of detection of displacement generation using vibration sensors show that the timing of collapse is faster than the method using laser sensors. If ground displacement measurements using sensors are continuously carried out in preparation for landslides, it is considered highly likely to be utilized as basic data for predicting slope collapse, reducing damage, and activating the measurement industry.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.400-421
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• 2019

This study was conducted to find out the seasonal distribution characteristics of meiobenthic communities to understand the benthic ecosystem of Gwangyang Bay, one of the representative bays in the southern coast of Korea. The faunal sampling was conducted eight times seasonally at 20 stations from 2010 to 2011. Among the meiobenthic fauna that appeared during the study period, the nematodes and harpacticoids were the most dominant. In the summer of 2011, the lowest density ($13ind.10m^{-2}$) was seen at station 10 on the inner part of the bay. In the winter of 2011, the highest density ($3,109ind.10m^{-2}$) was seen at station 4 on the inner part of the bay. Although the trend of seasonal changes in density was not clear, the meiobenthic community was seen to be affected more by the environmental factors in each season. Particularly, while the density of the harpacticoids, a dominant faunal group, showed negative correlations with the organic content and average particle size in the summer sediments (p<0.05, p<0.01), the density of the nematodes showed no significant correlation with the environmental factors except with the winter average particle size and the bottom layer's water temperature. The density change of meiobenthos showed irregular changes in Gwangyang Bay, instead of a general trend showing a low density in winter due to low water temperature but an increased density in spring and summer when the water temperature rises and a decreased one again in fall. Considering such a seasonal trend, it seems that the benthic ecosystem of Gwangyang Bay is affected more by artificial environmental factors than by natural environmental ones.

• Journal of the Korean Geosynthetics Society
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• v.18 no.1
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• pp.79-89
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• 2019

The field measurement and laboratory experiment were conducted to investigate the effect of reducing the surface temperature of the functional aspect of the heat island phenomenon of the permeable block which is made the recycled synthetic resin rather than the existing concrete permeable block. Field measurement was taken for 3 days in consideration of dry condition and wet condition and laboratory experiment was divided into dry condition, rainfall simulating condition, and wetting condition. The variations of temperature and the evaporation rate of water moisture content after experiment were confirmed. As a result of field measurement, it is confirmed that the surface temperature decreases due to the difference in albedo of the pore block surface rather than the cooling effect due to the latent heat of vaporization. The evaporation of moisture in a dry state where drought persisted or a certain level of moisture was not maintained in the surface layer. As a result of laboratory experiment, resin permeable block gives higher surface temperature when it is dry condition than concrete permeable block, but the evaporation of water in the pore is kept constant by capillary force in rainfall simulation condition, and higher temperature reduction rate. As a result of measuring the evaporation rate after laboratory experiment, it is confirmed that the effect of reducing temperature is increased as the evaporation rate of water is higher. Based on these results, correlation formula for evaporation rate and temperature reduction rate is derived.

• Journal of Korean Society on Water Environment
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• v.35 no.2
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• pp.145-151
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• 2019

The purpose of this study was to investigate treatment characteristics of diatomite filtration, that would allow water recovery from biologically-treated effluent for reuse. Diatomite, Celpure 100, and acid clay were used as filter-aids, with a support filter manufactured from polyethylene (PE), and polypropylene (PP). This pre-coating process using diatomite filter-aids, is used in the filtration range of pressure filters, and has consistently provided high-quality separation. The results showed that variations in average removal efficiency of SS, and T-P from biologically treated effluent by the diatomite-coated PE filter, were approximately 82.2 ~ 88.9 % and 4.8 ~ 21.1 %, respectively. T-P treatment efficiency of the PP filter pre-coated with diatomite and $Celpure^{(R)}100$ at $57.64g/m^2$, was approximately $24{\pm}10%$ and $40{\pm}15%$ on average, respectively. Particle size distribution of secondary effluent varied from 0.05 to $200{\mu}m$, and $d_{50}$ value was $20.76{\mu}m$. The size distribution of particles in the diatomite filtrate ranged from 1.26 to $101.1{\mu}m$ when pre-coated with diatomite filter-aid, at a content of $57.64g/m^2$. Diatomite filter aids, i.e., the particles that form the pre-coating layer, capture very fine particles as well as macromolecules, owing to their complex structure with numerous fine microscopic pores, and surface properties. The filtration process using diatomite and $Celpure^{(R)}100$ as filter aids, has been successfully applied, to recover water from sewage for reuse. The disadvantage of the process, is that the particle size of the filter-aid is spent, because of pressurization.